Joey Barton has apologised for a series of "offensive" and "untrue" comments he made on Twitter about the former Germany international Dietmar Hamann.

The row flared on Monday after Barton tweeted a response to the news that his Marseille team-mate Loïc Rémy had chosen to join QPR ahead of Newcastle, suggesting Newcastle's managing director Derek Llambias might be one of the reasons the France international did not move to the north-east club.

Hamann replied to tell him to keep out of the politics of his former clubs, sparking a bitter row involving more than 50 tweets, with Barton making a series of personal allegations and insinuations about the former Liverpool midfielder as well as calling him a "maggot", a "dog" and a "blert". He added: "You've got more front than Harrods."

Barton has since posted a statement on his personal website to apologise for the incident.

It read: "On Monday evening tweets exchanged between Dietmar Hamann and I went beyond the boundaries of banter, opinion and common sense. I accept that my comments were offensive, untrue and related to matters of a personal nature, of which I had no knowledge.

"I have apologised to Dietmar personally and now wish to apologise through the same social media channels that I used to make them, as well as my own website. I appreciate my comments have caused Dietmar and his family some distress and I fully regret that.

"I also appreciate that my comments should not have been made, as they could have damaged Dietmar's reputation, which should remain intact as a fantastic player and ambassador for German football, as well as the game in general. Dietmar and I have now agreed to draw a line under the unfortunate exchange and neither of us will be making any further comments on the subject."

Barton and Hamann played together briefly at Manchester City. Barton is currently on loan at Marseille from QPR after the club lost patience with him following his high-profile dismissal against City on the final day of last season and for his subsequent behaviour.